Analysis on Various Enzymes Involoved in Biodegradation of Lignocellulose by Fungal Isolates from Wood and Soil

Research Article
S.Prabhakar, C.Kandeepan* and P.Sivamani
Biodegradation, Lignocellulose, Wood- Soil Fungi, lignin peroxidase, manganese peroxidase, laccase

Three fungal strains that produced ligninolytic enzymes were isolated from palm oil plantation soils. Isolate MIRT 1 was identified as Aspergillus niger isolate MIRT 2 was identified as Aspergillus flavus, and isolate MIRT 3 was identified as Trichoderma viridae. These strains utilized lignin as the sole source of carbon and produced the main ligninolytic enzymes; lignin peroxidase, manganese peroxidase, and laccase. Based on the results obtained in this study, the isolate Aspergillus niger MIRT 1 was chosen as the best of the ligninolytic fungal strains, as it achieved maximum manganese peroxidase production of 2221.4 U/L on the third day under the optimum conditions of pH 8 and 30 ºC. Strain Aspergillus niger MIRT1 also produced the highest lignin peroxidase, at 204.45 U/L, on the fifth day of fermentation under the optimum conditions of pH 8 and 30 ºC. Strain Aspergillus flavus MIRT2 showed the highest laccase enzyme production of the three selected fungal strains in the present study. Although the production of manganese peroxidase and lignin peroxidase by strain Aspergillus flavus MIRT2 was lower than Aspergillus niger MIRT1, Aspergillus flavus MIRT2, Trichoderma viridae MIRT3 showed the highest laccase enzyme at 11.12 U/L on the fifth day under the optimum conditions of pH 7.5 and 35 ºC. The Trichoderma viridae strain has been considered a novel ligninolytic fungal isolate from palm oil plantation soil. Phanerochaete chrysosporium Standard culture showed bet results compared to the isolates though the isolates compete with that. For any environment if there is a mixture of these fungi then there will be great degradation of lignocellulose, which could be used commercially and/or industrially.